chmod 436 Permission Explained
Summary: chmod 436 gives the owner read, the group write/execute, and everyone else read/write.
| Class | Read (4) | Write (2) | Execute (1) | Octal |
|---|---|---|---|---|
| Owner (u) | 4 | |||
| Group (g) | 3 | |||
| Others (o) | 6 |
chmod 436 filename
chmod 436 Breakdown
| Class | Digit | Symbolic | On a file | On a directory |
|---|---|---|---|---|
| Owner (u) | 4 |
r-- |
Read only | Can list names, but not enter |
| Group (g) | 3 |
-wx |
Write and execute | Can enter and create/delete files, but not list |
| Others (o) | 6 |
rw- |
Read and write | Can list names, cannot enter |
Is chmod 436 Safe?
Critical Risk
- Anyone on the system can modify or replace this file.
- Every member of the group can modify this file.
- Any user can read this file — never use it for secrets such as keys or .env files.
- Even the owner cannot modify this file without changing permissions first.
- Unusual: a lower class has permissions the class above it lacks.
Common Use Cases
436 is uncommon in standard Linux setups. The closest widely used permission is chmod 666.
chmod 436 Command Examples
# Apply using octal mode
chmod 436 filename
# Apply using equivalent symbolic mode
chmod u=r,g=wx,o=rw filename
# Recursive command warning:
chmod -R 436 /path/to/dir
# Note: -R applies the same mode to files and directories. Use find to treat them separately:
find /path/to/dir -type f -exec chmod 436 {} +
# Verify permissions
stat -c '%a %A %n' filename # Linux
stat -f '%Lp %Sp %N' filename # macOS
# Example ls -l output:
-r---wxrw- 1 alice staff 1024 Jan 15 10:00 example.txt
umask Relationship
A umask of 341 makes new directories 436. Test umask values with our interactive Umask Calculator.
Frequently Asked Questions
What does chmod 436 mean?
chmod 436 gives the owner read, the group write/execute, and everyone else read/write. In octal notation, the owner receives 4 (read), the group receives 3 (write/execute), and others receive 6 (read/write).
Is chmod 436 safe?
chmod 436 is classified as Critical Risk. Anyone on the system can modify or replace this file.
What is chmod 436 in symbolic notation?
In symbolic notation, chmod 436 is represented as r---wxrw-. You can apply this permission using the equivalent symbolic command "chmod u=r,g=wx,o=rw filename".
Related Permissions
Change one bit: